While secret societies have terrific members-only benefits, their gorilla-centric initiation rites are often illegal. Make a solemn fitness vow that's legal with today's Groupon: for $25, you get five spinning classes at Go Cycle Studios (a $59.50 value).

With drive-in season fast approaching, you’ll want to make sure your thighs and glutes are strong and able to support your frame in upcoming hours-long Fellini marathons. The Royal Oak spinning studio offers a bevy of bike-mounted classes to suit any level of rider. Pedal-pushing novices can try out Intro to GoCycle, which teaches the basic technique, bike-riding etiquette, and spinning slang. More-advanced riders can take a variety of classes, including GoCycle Hills, an exactly-what-it-sounds-like resistance spinning session for maniacal muscle builders. The fun and high-energy classes are led by Go Cycle’s supportive instructors, who shout encouragement and inject motivation directly into tired muscles.

The state-of-the-art studio features a sleek, industrial décor, with exposed-brick walls and reflective hardwood floors, and its high-end collection of bikes come fully equipped with multi-functioning monitors that keep track of your vital stats while quietly whispering inspirational movie quotes to you as you ride. The bountiful daily class schedule offers exercising options for even the most highly booked banker, and to ensure availability, bikes can be reserved online prior to class.

New clients only. Bring a towel and water bottle to class.